OBJECTIVES: A study in an animal sepsis model: a) the immunologic status of the host by evaluating lymphocyte subpopulation dynamics; and b) metabolic alterations and possible interactions with immunologic processes. 2) To study surgical patients, trauma patients and patients with sepsis to: a) detect alterations in immunologic constitution and function and correlate to the incidence and extent of infectious complication; and b) define metabolic alterations and determine the nature of myocardial failure in sepsis.